Bell RingerBell Ringer

Sports announcers will occasionally Sports announcers will occasionally say that a person is accelerating if say that a person is accelerating if he/she is moving fast. Why is this not he/she is moving fast. Why is this not an accurate description of what an accurate description of what acceleration is?acceleration is?

ObjectivesObjectives

DefineDefine acceleration in words and acceleration in words and with an equationwith an equation

IdentifyIdentify positive and negative positive and negative acceleration by analyzing a graphacceleration by analyzing a graph

CalculateCalculate acceleration with the use acceleration with the use of an equation and graph of an equation and graph

DefineDefine and and applyapply the force of the force of gravitygravity

Change in VelocityChange in Velocity

Each time you take a step Each time you take a step you are _________________ you are _________________ the _____________ of your the _____________ of your body.body.

You are probably most You are probably most familiar with the velocity familiar with the velocity changes of a moving bus changes of a moving bus or car.or car.

The rate at which _________ The rate at which _________ (__________ or __________) (__________ or __________) changes occur is called changes occur is called _______________________._______________________.

Acceleration= Acceleration= ________ ______ ________ ________ ______ ________ ____________

Change in velocity = final Change in velocity = final – – starting starting

velocity velocity velocity velocity

Acceleration= Acceleration= ____________________________________________________

Acceleration =Velocity(final) - Velocity(original)

time

A car traveling at 60 mph accelerates to90 mph in 3 seconds. What is thecar’s acceleration?

=

=

=

Acceleration =Velocity(final) - Velocity(original)

time

A car traveling at 60 mph slams on the breaks to avoid hitting a deer. The car comes to a safe stop 6 seconds after applying the breaks. What is thecar’s acceleration?

=

=

=

- A _________________ - A _________________ acceleration produces acceleration produces

a __________ line or a __________ line or linear slope linear slope

(_______________). (_______________). - The ________ of a - The ________ of a

non-linear velocity-non-linear velocity-time graph (rise/run) time graph (rise/run) will predict an objects will predict an objects

instantaneous instantaneous ____________________. ____________________.

a = /a = /Calculate the Calculate the instantaneous instantaneous

acceleration of the graph: acceleration of the graph:

a = v/ta = v/t

a =a =

a =a =

Free fallFree fall The constant ___________________ The constant ___________________

of an object moving only under of an object moving only under the force of _______________ is the force of _______________ is "g". "g".

The acceleration caused by The acceleration caused by ____________ is _____ m/s____________ is _____ m/s22

If there was no _________, all If there was no _________, all objects would fall at the same objects would fall at the same ________________________

Doesn’t depend on ____________Doesn’t depend on ____________ After 1 second falling at 10 m/sAfter 1 second falling at 10 m/s After 2 seconds ________ m/sAfter 2 seconds ________ m/s 3 seconds _________ m/s3 seconds _________ m/s

GalileoGalileo

1600’s 1600’s Studied how things fellStudied how things fell Didn’t have a good Didn’t have a good

clockclock Rolled balls down an Rolled balls down an

_______________ plane_______________ plane Found that the Found that the

___________ increased ___________ increased as it rolled __________ as it rolled __________ the rampthe ramp

GalileoGalileo

t = 0t = 1 second

t = 2 seconds

t = 3 seconds

Acceleration= Acceleration= ________________________________________________________

GalileoGalileo

Same things happen when Same things happen when things fallthings fall Didn’t drop things from Tower of Pisa

FallingFalling ______ resistance will ______ resistance will

increase as it falls increase as it falls ____________________________

An ________________ An ________________ force on the objectforce on the object

Eventually __________ Eventually __________ will ______________ with will ______________ with _______ resistance_______ resistance

Reaches _____________ Reaches _____________ velocity - highest velocity - highest speed reached by a speed reached by a falling object.falling object.

Terminal velocityTerminal velocity Force of gravity is Force of gravity is

constantconstant air resistance ___________ as you speed up until the force is _________

_____________ forces, no ________________________ ______________ velocity _______________ velocity

_______________ Velocity and _____________ Acceleration

__________________ Velocity and ______________ Acceleration

_________________ Velocity and ______________ Acceleration

____________________ Velocity and _______________ Acceleration